Vista - Vista graphics card crashing

A few weeks ago, this problem started.
Whenever I'm chatting on IMVU, or doing anything which requires lot of 3D, my screen flickers 2 or 3 times, I see everything freezed, the screen turns black, and then most of the time, after a while, it turns back and gives me a balloon message on the taskbar that the graphics' driver stopped responding and is restored.
It happens a lot.
And it gives on my nerves a lot, because when the screen returns, all 3D using programs are not responding anymore, untill I try to close it, and tell Windows Vista to wait untill it responds, then it takes about a minute or 2 to see motion again.
Sometimes the error doesn't happen at all. Sometimes it happens every 5 minutes. And I even had a blue screen once.
The only thing I was able to read was that the graphics' driver stopped responding and Windows was unable to restore it.
I tried reinstalling the driver.
But didn't help.
I own the newest version of the driver, so update is not possible.

How can I solve this?
Can anybody help me?

read the couple of other posts right at the top right now that discuss this also. check to make sure there is good airflow in the case that there is no dust build up and things like to that to make sure it is not a temperature problem

this sounds like an issue that i have been having as well. i thought it was mainly due to the fact that my sound card crackles and makes my display driver stop. thats the good 'ol issue with creative and nvidia. but it now seems like it could be that 186.18 driver in some cases as well. i get the flickering and the blackscreen all after a while, not as fast as he said he did. but if its not only in SLI like mine, then something in the driver perhaps causes this?

How to check temperature?
Dust is out of the question, the computer isn't a month old

do a search for everest ultimate and look at your temperatures with it. are you overclocking? have you tested the memory?

also look through this thread "display driver atikmdag stopped responding and has successfully recovered" error

I dunno if it's something to do with the SLI, 'cus when I listen to music in media player, nothing changes to the song or the quality, it just keeps playing, it stops for several seconds, probably while the restore of the not responding driver is busy, but the song just resumes and continues playing.
Another reason why I don't think SLI is the issue, is because, today, I got the error 1 or 2 times.
I remember 1, and i wasn't playing any sounds at all, after the error, i just kept on using IMVU (3D chat messenger) while running WMP11 at the same time.
I didn't got an error anymore (for today)
So I think it isn't the SLI
What you mean with creative and NVIDIA?
I kinda got confused there
And do you mean like Creative (mp3-player's driver?)

I'm not overclocking, and what do you mean with a memory test?

copy the error code down and post it here

test your system memory with memtest86